Printing apparatus



July 12, 1960 J. K. BRUCE PRINTING APPARATUS Filed Maren 11, 1957 as end seal 49 makes sliding contact with the printing roller surface and prevents passage of the solvent contained in the Well between the side of the well `and the roller.

The front wall of the solvent well is considerably lower than back wall 43. Attached to the inner surface of the front wall is a rst solvent barrier 51 shown in substantially tangential contact with the surface of the printing roller. The irst barrier extends parallel to the axis of the printing roller from end seal to end seal of the solvent well. The first solvent barrier may be a strip of thin flexible material and not only serves as a partial front Wall of the solvent well, but when in proper contact with the printing roller, prevents the pigment solvent in the well lfrom coursing ldownwardly along the surface of the Vprinting roller to the region of printing contact of the roller with the material.A

A second solvent barrier 55 is held in substantially tangential contact with the surface of the printing roller between the solvent well and the region of contact between the printing roller and the pattern roller. The second solvent barrier may be a thin flexible metallic strip extending parallel to the axis of the printing roller from end seal to end seal.

The second solvent barrier is heldin movable contact with the printing roller by a pair of L-shaped brackets such `as bracket 57 pivoting about a rod SSextending between printing framegends 12. yA screw and crank 59v are connected to bracket 57. RotationV of the crank changes the position of the second barrier.

It is preferable that the solvent be circulated in the well so that fresh solvent is maintained against the surface of the printing roller. Therefore, a pump 61 adapted to move'solvent from a reservoir 63 to a bottom inlet65 ofthe solvent well is regulated by conventional means to provide a measured flow of solvent vinto the well. An upper overow 67 returns the same measure of solvent to the reservoir. Various reclamation means such as tilters'may be used to insure a supply of effective solvent from the reservoir to the well.

The rails 37 sliding in ways 39 are preferable to adjust the position of first solvent barrier 51 and the solvent well with respect to the surface of printing roller 16. The left hand end of each rail, as viewed in the gure, has a rack portion 71 meshed with a spur gear 73` turnable by means not shown.'V Rotation of spur gear 73 moves rail 37 within the way .and changes the contact of irst solvent barrier 51 with the printing roller.l A shaft 74 connects spurgear 73 to a like gear meshed with like components on the opposite side of the frame (not shown) so that the well moves smoothly. Rotation in counterclockwise direction'removes the solvent well and the first barrier from proximity with the printing roller. The positions of the second solvent barrier and the pigment Well with respect to the printing roller and the pattern roller are changeable. Each may -be moved so that the contact pressure against the instant roller is increased.

Conversely, each may be moved from Contact with the roller. The provisions for adjustment of the solvent well, the solvent barriers and the pigment Well make possible convenient substitution of different rollers in the printing frame. K

In operation the rotogravure pattern roller is pigmented by the pigment well and rotates into contact with the printing roller. The printing roller receives the pattern impression and pigment from the pattern roller and rotates into contact with the material to be printed. The pressure vroller insures Vcontact of the material with the printing roller and transfer of the pattern is effected as the material passes between the printing and pressure rollers. The surface of the printing roller with whatever residual pigment remains on the surface, then revolves into the regionof contact with the solvent in solvent well 3'57. liev front wall of the solvent well differs sufficiently from thel back wall inv height so that a substantialV area of solvent is in contact with the printing roller surface. The lsolvent dissolves the residual pigment and a clean printing roller results. The rst solvent barrier precludes leakage of solvent downwardly toward the material and the second solvent barrier contacts the printing roller surface so that no solvent `is carried by the printing roller into the region vof patterning contact.

Therefore, the printing surface roller presented to patterning contact with the pattern roller is free of any residual material, and a perfect pigment and pattern imprint may be transferred to the surface of the printing roller. No design fuzziness is present when the cleansed pattern portion-of the roller imprints upon the material. TheV ability of the printing Toller to transfer a finely detailed pattern is increased because the continuously cleansed roller surface takes and imparts a more exact pattern.

I claim:

1. In an apparatus for transferring a continuous pigmented design to a material, a pattern roller, a pressure roller, a4 gelatinous printing roller vertically disposed above the pressure roller, said printing roller impressing v the surface of the material as the material passes-between the-printing-roller and the pressure roller, means for continuously pigmenting the pattern roller, a pigment solvent well coextensive with the effective length oft-he printingroller, a-rst solvent barrier co-extensive with j the effective length of the printing roller and supported by the pigment solvent well, a second solvent barrierfco-` extensive with the effective length of the printing roller, and Vseals adjacent each Lend of the printing roller precluding passage of pigment solvent from the solvent well at the ends of the printing roller, the solvent well being positioned with respect to the printing roller so that a peripheral segment of the printing roller surface travelling from the region of contact with ,the material toward patterning contact with the pattern roller is directly contacted by a pigment solvent contained in the solvent well to wash from the printing roller pigment carried over from the printing contact with the material.

2. In an apparatus for transferring a continuous pigmented design to a material, a pattern roller, a pressure roller, a gelatinous printing roller vertically disposed above the pressure roller, said printing roller impressing the surface of the material as the material passes between the printing roller and the pressure roller, means for continuously pigmenting the pattern roller, a pigment solvent Wellco-extensive with the effective length of the printing roller, the solvent well being positioned with respect to the printing roller so that a peripheral segment of the printing roller surface travelling from the region of contact with the material toward patterning contact with the pattern roller is directly contacted by a pigmentsolvent contained in the solvent well, a rst solvent barrier coextensive with the effective length of the printing roller and supported by the pigment solvent Well, a second solvent barlrier co-extensive with the effective length of the printing roller, seals adjacent each endof the printing roller precluding passage of pigment solvent from the solvent well. at the ends of the printing roller, means for adjustably positioning the rst solvent barrier relative to the surface of the printing roller and means for adjustably positioning the second solvent barrier relative to the surface of the printing roller. Y

References Cited in thele of this patent Y UNITED STATES PATENTS 783,580 Herzog Feb. 28, 1905 1,154,002 Crump et al Sept. 21, 1915 1,807,894 Casto et al lune 2, 1931 2,363,817 Taylor Nov. 28, 1944 2,574,002 `Weiss Y ..V.. f Nov. 6, 19.51

- V FOREIGN PATENTS 5,311AV Great Britain 1 Mar.` 4, 1898 

